Laser welding method

Patent metadata

Field	Value
Publication number	US-10286491-B2
Application number	US-201515118630-A
Country	US
Kind code	B2
Filing date	Feb 23, 2015
Priority date	Feb 25, 2014
Publication date	May 14, 2019
Grant date	May 14, 2019

Abstract

A laser welding method of the present disclosure has a first step and a second step. In the first step, a first workpiece and a second workpiece are overlaid in a first machining region. In the second step, the first workpiece and the second workpiece are irradiated with laser beam in the first machining region while the laser beam is moved in a spiral path. Moreover, in the second step, the first workpiece and the second workpiece are melted by irradiation of the laser beam to form a liquid phase portion. Furthermore, in the second step, the laser beam is moved so that the liquid phase portion is not irradiated with the laser beam again.

First claim

The invention claimed is:

1. A laser welding method comprising:
a first step of overlaying a first workpiece and a second workpiece in a first machining region; and
a second step of irradiating the first workpiece and the second workpiece with a laser beam in the first machining region while the laser beam is moved in a spiral path,
wherein in the second step,
the first workpiece and the second workpiece are melted by irradiation of the laser beam to form a liquid phase portion, and
the laser beam is moved so that the liquid phase portion is not irradiated with the laser beam.

2. The laser welding method according to claim 1 , wherein an interval between paths adjacent to each other in a radial direction of the spiral path is equal to or larger than a beam diameter of the laser beam and twice or smaller than the beam diameter of the laser beam.

3. The laser welding method according to claim 1 , wherein an inner end of the spiral path is different from a center of the first machining region.

4. The laser welding method according to claim 3 , wherein a distance between the inner end of the spiral path and the center of the first machining region is greater than a radius of an irradiation diameter of the laser beam.

5. The laser welding method according to claim 1 , wherein the interval between the paths adjacent to each other in the radial direction is longer toward an outer side of the spiral path.

6. The laser welding method according to claim 1 , wherein in the second step, a moving speed of the laser beam is faster toward the outer side of the spiral path.

7. The laser welding method according to claim 1 , wherein an output of the laser beam is lower toward the outer side of the spiral path.

8. The laser welding method according to claim 1 , wherein in the second step, the laser beam moves from an inner side of the spiral path to the outer side of the spiral path.

9. The laser welding method according to claim 1 , wherein in the second step, the laser beam moves from the outer side of the spiral path to an inner side of the spiral path.

10. The laser welding method according to claim 1 , comprising:
a third step of overlaying a third workpiece and a fourth workpiece in a second machining region; and
a fourth step of irradiating the third workpiece and the fourth workpiece with a laser beam in the second machining region while the laser beam is moved in a spiral path,
wherein in the fourth step,
the third workpiece and the fourth workpiece are melted by irradiation of the laser beam to form a liquid phase portion,
the laser beam is moved so that the liquid phase portion is not irradiated with the laser beam again,
a gap exists between the first workpiece and the second workpiece in the first machining region,
the third workpiece and the fourth workpiece are in contact with each other in the second machining region,
a first moving speed of the laser beam in the second step is faster than a second moving speed of the laser beam in the fourth step, and
a first output of the laser beam in the second step is higher than a second output of the laser beam in the fourth step.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Nakagawa Tatsuyuki
• Mukai Yasushi
• Kawamoto Atsuhiro
• Fujiwara Junji
• Matsuoka Noriyuki

Classifications

• B23K26/22

  Spot welding · CPC title

• B23K26/0876

  in at least two axial directions · CPC title

• B23K26/082

  Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head · CPC title

• B23K26/0626

  Energy control of the laser beam (B23K26/0622 takes precedence) · CPC title

• B23K26/244 Primary

  Overlap seam welding · CPC title